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Video CD

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Compact Disc Digital Video (VCD)
A standard pressed compact disc
Media typeoptical disc
EncodingMPEG-1 video + audio
Capacityup to 800 MiB
Read mechanism780 nm wavelength semiconductor laser
Developed bySony & Philips
Usageaudio and data storage
VCD redirects here. For other uses, see VCD (disambiguation)
This article is about the all-digital 'Video CD' format. For the earlier (and less successful) analog/digital hybrid, see CD Video.

Video CD (aka VCD, View CD, Compact Disc digital video) is a standard digital format for storing video on a Compact Disc. VCDs are playable in dedicated VCD players, nearly all personal computers, most modern DVD-Video players, and some video game consoles.

The VCD standard was created in 1993 by Sony, Philips, Matsushita, and JVC and is referred to as the White Book standard.

Technical specifications

Video

Overall picture quality is intended to be comparable to VHS video, though visual artifacts may be noticeable in some cases. Poorly compressed video in VCD tends to be of lower quality than VHS video, but exhibiting block artifacts rather than analog noise.

352 horizontal pixels was chosen because it approximates the resolution of an analog broadcast video signal, assuming a 5 MHz bandwidth. Any more than this would be wasted in the RF modulator, which was the usual means of video input for domestic television receivers at the time.

VCD video is mostly compatible with the DVD-Video standard, except for any video encoded at 23.976 frames per second. DVD-Video requires all MPEG-1 video to be encoded at either 25 or 29.97 frames per second.

Audio

As with most CD-based video formats, VCD audio is incompatible with the DVD-Video standard due to the difference in frequency; DVDs require 48 kHz, whereas VCDs use 44.1 kHz.

Other information

Video CDs are authored (or "burned") using the Mode 2/XA format, allowing roughly 800 megabytes of VCD data to be stored on one 80 minute CD (versus 700 megabytes when using Mode 1). This, combined with the net bitrate of VCD video and audio, means that almost exactly 80 minutes of VCD content can be stored on an 80 minute CD, 74 minutes of VCD content to a 74 minute CD, and so on. This was done in part to ensure compatibility with existing CD drive technology, specifically the earliest "1x speed" CD drives.

Similar formats

The DVCD or Double VCD is designed to squeeze the most out of a CD. A non-standard CD is overburned to include up to 100 minutes of video. This format is seen only in China (although such titles can be found outside China, they're extremely rare), and the DVCDs are playable on many DVD or VCD players. However, some CD-ROM drives and players have problems reading these CDs, mostly because the groove spacing is outside specifications and the laser servo is unable to track it.

The XVCD (eXtended video CD) does not act around standard-conforming video CD (VCD) for storage of video data on a normal CD-ROM or CD-R (W), and thus offers a longer playing time.

A normal VCD is coded in the MPEG-1 format with a constant bit rate (CBR); i.e. all scenes are encoded with a standard 1150 kbit/s videostream independent of the content, whether it is a fast, movement-rich scene or a mostly-static, fixed-image scene.

The eXtended VCD is coded with a variable bit rate (VBR); i.e. the bit rate for fast scenes can be raised to approximately 2000 kbit/s, however, with very calm scenes it may drop to 300 kbit/s. In addition, one works with a changed Quantize matrix and around further storage location will win the bit rate of the MP2-Tons reduced, as well as if necessary additionally extended the GOP (Group OF Pictures).

By implementing these changes a feature of approximately 2 hours of length can be accommodated on only one CD.

Besides VCD there are further variants for resolutions from 352 × 288 to 720 × 576 pixels and for the television standards PAL and NTSC, which are found under the column “eXtended”. Colloquially, XVCD for MPEG1, VCD resolution and a 1-CD datasize for a video file became generally accepted.

By close compliance (here “variable bit rate”) to the SVCD standard most DVD players can play XVCDs in the VCD resolution (352x288 PAL and/or 352x240 NTSC). Historically this extension of the format comes from the Asia, in order to store and show complete feature films on the simplest videoplayer using CDs, without incurring DVD licensing fees.

XVCD variants (XVCD, MVCD, KVCD, AVCD…) essentially differ by resolution, bit rate, GOP and the assigned Quantize matrix. Here attention should be paid if necessary to possible compatibility problems, e.g. within the range of permitted resolutions and/or extreme GOP values. MVCD/KVCD, e.g. CD formats (VCD), are priority. The DVD video specification is considerably stricter and leads to potential playing errors. This is very dependent upon DVD player model.

The background of the development began with the first availability of cheap DVD players in the East, which were not only limited to the rendition of not pressed DVD and video CD, but for the first time could show video CDs, MP3-Data and pictures also burned to CD. One of the first surface-covering Multiformat Players appeared in the trade was (predominantly from existing PC components) the Yamakawa AVPhile 713/715. The equipment did not take it not so exactly with playing conformal CDs, while DVD Player burned blanks rejected other standard immediately. By those ever more largely becoming fan municipality of the Players arose the desire to burn and play more highly dissolved and own video material.

The largest hurdle was however the refusal of the usual burning programs of the day to be able to burn non-conforming MPEG1 video CD Streams. These were rejected directly with a lapidary error message. A lengthy search of all the burning programs available on the market succeeded by exchanging a certain older DLL of the CD burning program NTI CDMaker, overcoming this barrier so that everyone could burn non conformal video CD formats. Even mixed from MPEG2-Stream, burned as MPEG1 video CD was possible (creating XSVCD or eXtended super video CD); also toward 6-Kanal files on MPEG1 video CD basis one researched, failed however because of the conversion Tools needed for it.

The solution method for the production of a XVCD was made accessible after long test runs in the spring 2000 in the DVDBoard.de of the public for the first time and assigned to the again gekürten video CD standard the designation XVCD (eXtended video CD). From there from distributed itself the production a XVCD with better image quality and higher data rate soon around the whole world. Manufacturers in the following published devices recruited generously with the support standard XVCD, technical periodicals wrote guidances for production such film home CDs and also update of usual burning programs finally permitted non-conformal video files.

Since the use of the MPEG1-Formats with high data rates found however many standard Player overtaxed and the format SVCD on MPEG2 basis, as well as the rendition of DivX AVI files slowly to spreading, providing/burning these drilled out video files took care of itself with the time and today is not no more used. Likewise the availability displaced the use/use of selbsterstellter video CDs of DVD burners for home users.

(x)VCD

There are many non standard variants of the standard Video CD. Those called (x)VCD and they supported by most (but not all) standalone DVD players.

Popular (x)VCD are KVCD, CVCD (a Spanish xVCD), S(x)VCD (a VCD but with vbr mpeg 2) and miniDVD. There is also SKVCD (or KSVCD) which does much the same thing as KVCD, but uses MPEG2 and adds some luxuries such as multiple audio streams and chapters. Some later flexible standalone players now support (K)SVCD, as the format has been endorsed by Philips, the custodian of all the CD standards.

Most commonly the players can have trouble with (x)VCDs.

SXVCD

Super eXtended VCDs are another hack of VCDs. They have the same bitrate as DVD (9.8 Mbits per second) and are read by most DVD players. The only major disadvantage is that very little video can be stored on an SXVCD and is therefore often used for short home videos.

Adoption

While never gaining a foothold in the United States, Europe or Japan, commercial VCDs are very popular throughout Asia (except Japan) because of the low price of the players, their tolerance of high humidity (a notable problem for VCRs), and the lower-cost media. Ease of duplication and the negligible cost of the media gave rise to widespread unauthorized copying in these areas.

Available long before DVD-Video, digital VideoCD might have replaced analog VHS as the dominant home video format in United States by the mid-1990s. However, because VCDs have virtually no inherent copy prevention, the format was actively and successfully squashed in the US by the feature film industry. Subsequently, the US entertainment industry refused to support DVD-Video until it incorporated multiple layers of copy prevention, holding up DVD-Video's release to the general public for several years.

The advent of recordable CDs, inexpensive recorders, and compatible DVD players spurred VCD acceptance in the US in the late 1990s and early 2000s. However, DVD burners and DVD-Video recorders were available by that time, and equipment and media costs for making DVD-Video fell rapidly. DVD-Video, with its longer run time and much higher quality, quickly overshadowed VCD.

With the advent of CD burners becoming standard on home PCs, plus the wide availability of low-cost MPEG-1 capture devices, VCD was the first digital video recording format that was widely available to consumers. However, many DVD players made before 2003-2004 could not read recordable (CD-R) media, and this limited the compatibility of VCD. Almost every modern stand-alone DVD-Video player can play VideoCDs burned on recordable media.

Many commercial Video CDs of blockbuster Hollywood, Bollywood, Manilawood and other Asian movies and television series are not widely available in the Western countries; however, they are available in certain ethnic communities and several commercial web sites (although quality and authenticity may sometimes be questionable). These VCDs are often produced and sold in Asian countries such as Pakistan, Hong Kong, Mainland China, Thailand, Malaysia and the Philippines. In many Asian countries, major Hollywood studios (and Asian home video distributors) have licensed companies to officially produce and distribute the VCDs, such as MCA Home Video in Pakistan, ERA of Hong Kong or Sunny Video in Malaysia, Berjaya-HVN and InnoForm Media in both Malaysia and Singapore, as well as VIVA Video, Magnavision, and The Video to C in the Philippines. Legal Video CDs can often be found in established video stores and major book outlets in most Asian countries.

Around 2003–2006 VCDs were given away by Greek newspapers to boost declining sales. Because of this documentaries, films and even soft porn VCDs became very common in Greece.

Due to relative small storage capacity, feature-length films sold on VCD are usually divided into two or three discs and television series may come in a box set package with multiple discs. In both cases, most films run at roughly 60 minutes per VCD, before viewers are prompted to change discs. In many Asian movies, subtitles are not removable on standard VCDs, unlike DVDs.

VCD is gradually being replaced by DVD, which offers most of the same advantages to Asian buyers as VCD, as well as a much better quality picture (higher resolution with less digital compression artifacts) and sound (often in Dolby Digital and/or DTS), due to its larger storage capacity.

VCD does however have a few points in its favor:

  • Like VHS and unlike DVD-Video, the VCD format has no region coding. Many VCD players are capable of compensating for the different frame rate and pixel count between NTSC and PAL TV systems, which means that discs can be played on any compatible machine worldwide.
  • Some titles available on VCD may not be available on DVD and/or VHS in the prospective buyer's region.
  • They are much cheaper than DVDs. The DVD of a film may cost anywhere from three to nine times as much as the VCD.
  • VCD is also a very popular format for karaoke in East Asia, where picture quality concern is not paramount.

These factors may ensure a steady market for VCDs for many years to come.

References

See also

  • Super Video CD (SVCD) - The direct successor to Video CD
  • China Video Disc (CVD) - An alternative successor to Video CD
  • miniDVD - DVD video on a CD
  • DcVD - A non-standard MPEG-1 format for playback on one platform only
  • KVCD - A non-standard variant of Video CD with better storage capacity, supported by many modern standalone players
  • CD Video - a 1980s format combining the laserdisc and the CD
  • MovieCD - a commercial 1990s format using the MotionPixels codec
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